Automated ball mounting process and system with solder ball testing

Abstract

An automated ball mounting process and system are disclosed In which solder balls are tested by heating the solder balls to a temperature between the eutectic temperature of lead-tin and the melting temperature of a lead free solder ball. If the heated solder balls melt they are standard solder balls. If they do not melt they are lead free solder balls. Solder balls that are input into the automated ball mounting process are automatically tested to determine solder ball type. When the test indicates that the wrong type of solder ball is being used an error message is indicated and the solder ball mounting process stops.

Description

FIELD OF THE INVENTION [0001] The present invention relates to the field of semiconductor devices. More specifically, the present invention relates to solder ball mounting processes and systems. BACKGROUND ART [0002] Automated solder ball mounting systems have been developed that quickly and accurately attach solder balls to substrates. The solder ball type most commonly used in these systems is the standard solder ball. Standard solder balls are formed of a lead-tin alloy. However, for environmental reasons there has been an increasing need for the use of lead free solder balls. [0003] The requirement that a manufacturing facility be able to attach both standard solder balls and lead free solder balls has forced some manufacturing facilities to purchase additional dedicated ball mounting systems to mount lead free solder balls. However, when both standard solder balls and lead free solder balls are used in the same manufacturing facility, workers can accidentally input the wrong ty...

AI Technical Summary

Benefits of technology

[0006] The present invention provides an automated solder ball mounting process and system in which solder ball type is tested in order to assure that the correct type of solder ball is being used. This results in reduced down time and reduced defect rates.

[0007] An automated solder ball mounting process and an automated ball mounting system are disclosed in which solder balls are tested to determine solder ball type. When the test is performed and the wrong solder ball type is being used an error message is indicated and the solder ball mounting process is stopped. This prevents product defects that can result from the use of the wrong solder ball type. In addition, a single solder ball mounting system can be used to attach both standard solder balls and lead free solder balls while preventing product defects that can result from use of the wrong solder ball type. The use of a single system instead of two dedicated systems results in significant cost savings as compared to prior art processes that use one dedicated system for standard solder balls and a second dedicated system for lead free solder balls.

[0008] By preventing the attachment of the wrong solder ball type, the method and apparatus of the present invention results in reduced product defects. In addition the method and apparatus of the present invention allows for quicker start-up of the manufacturing process as there is no need to send-solder ball samples to a test lab and wait for test results.

Problems solved by technology

However, when both standard solder balls and lead free solder balls are used in the same manufacturing facility, workers can accidentally input the wrong type of solder ball into a solder ball mounting system.

This can result in numerous defective products being fabricated before the problem is discovered.

The lab test delays the start-up of production, reducing equipment utilization rates and reducing efficiency.

Moreover, though testing prior to start up of production assures that the production process will start off with the correct solder ball type it is still possible that a worker may input the wrong type of solder ball into the ball mounting system during production.

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